Social relation manifests when the relationships of persons with one another are established, reciprocated or deepened. The videos are becoming the mainstream medium to share information, which capture individuals with different social connections. Effectively exploiting such socially-rich sources can provide social facts other than the conventional medium-like text. Such a capability promises a wide spectrum of applications. For instance, an automatic social relation inference allows for relation mining from image collection in social network, personal album, and films.
The social relation traits or social relation defined in this application is based on the interpersonal circle proposed by Kiesler, where human relations are divided into 16 segments, but more attributes may be defined. Each segment has its opposite sides, such as “friendly and hostile”. Therefore, the 16 segments may be considered as eight binary relation traits. For instance, “friendly” and “competitive” are easily separable because of the conflicting meanings. However, some relations are close such as “friendly” and “trusting”, implying that a pair of faces may have more than one social relation.